Graduate School of Pharmaceutical Science , The University of Tokyo , Hongo, Bunkyo-ku, Tokyo 113-0033 , Japan.
Org Lett. 2019 Sep 20;21(18):7619-7623. doi: 10.1021/acs.orglett.9b02895. Epub 2019 Sep 9.
A mild radical-based coupling method was devised for intermolecular installation of quaternary carbons. Treatment of α,α-dialkoxyacyl telluride with EtB/O at room temperature promoted the formation of a highly reactive α,α-dialkoxy carbon radical, which coupled with 2-cyano-3-methyl-2-cyclohexen-1-one to forge the sterically cumbersome bond between the tetrasubstituted and quaternary carbon centers. The present convergent strategy was successfully applied to a seven-step total synthesis of 5--eudesm-4(15)-ene-1β,6β-diol ().
设计了一种温和的基于自由基的偶联方法，用于在分子间引入季碳。在室温下，用 EtB/O 处理α,α-二烷氧基酰基碲化物，促进了高反应性的α,α-二烷氧基碳自由基的形成，该自由基与 2-氰基-3-甲基-2-环己烯-1-酮偶联，在四取代和季碳中心之间形成了空间位阻较大的键。该收敛策略成功地应用于 5--桉叶烷-4(15)-烯-1β,6β-二醇（）的七步全合成中。
